Continuous Improvement Methodology Applied to United Kingdom Academic Library Websites Via National Survey Results

This article analyzes the possibilities of applying Continuous Improvement principles to the management and maintenance of academic library websites. Current practice is mapped onto Continuous Improvement principles, with evidence distilled from a United Kingdom national survey of academic library web practitioners. The survey data informs a website organizational framework and operational model. The framework describes the setting within which library websites are managed, while the model focuses on library specific aspects to the management and development of their site.     

A broad-band transmission line model for a rectangular microstripantenna

A method is developed using the transmission line model to predict the input characteristics of rectangular microstrip antennas over a wide band of frequencies. A series combination of transmission lines is used to represent each transverse magnetic (TM) model. Following a brief summary of the basic transmission line model, the idea of an equivalent length, width, and feed offset are introduced to model each mode. The results predicted by the model compared well with experimental results that assumed varying feed positions. The concept of equivalent length, width, and feed offset was validated by experimental results but shows that the equivalent offset term needs some improvement. The number of modes incorporated in the model depends on the frequency range over which the antenna must be modeled. Using three transmission lines gives good results up to the frequency at which the TM₀₂ mode is excited     

The corrosion-wear behaviour of thermally oxidised CP-Ti and Ti-6Al-4V

The use of commercial purity titanium (CP-Ti) and Ti-6Al-4V alloys in bio-medical implant applications has been limited by their poor resistance to surface degradation processes. In this paper the corrosion-wear behaviour of untreated and thermally oxidised CP-Ti and Ti-6Al-4V have been compared. Oxidation of both alloys at 625 °C for 36 h resulted in the formation of an exterior layer of TiO₂ (rutile) that had a hardness ∼1000 HV. Corrosion-wear tests were made in reciprocation sliding contact with an α-Al₂O₃ ball immersed in physiological saline (0.89% NaCl) at room temperature. The oxidation treatment retarded the corrosion-wear of both CP-Ti and Ti-6Al-4V. For the untreated alloys, surface damage was dominated by micro-asperity shearing which resulted in rapid wear. Corrosion-wear of the oxidised materials was slower but more complex. The exterior TiO₂ layer formed on the oxidised Ti-6Al-4V alloy provided little protection, it was rapidly removed during the first 60 min of testing, by a process involving interfacial fracture. Conversely, the TiO₂ layer, albeit thinner, provided protection for the oxidised CP-Ti. Here, the layer becomes smoothly worn by a process that is proposed to be caused by the mechanical dissociation of the TiO₂-layer. For both oxidised titanium alloys the hardened oxygen diffusion zone (ODZ), formed beneath the TiO₂ layer, provided good protection from corrosion-wear. In both cases the ODZ was smoothly worn by a combination of abrasion and corrosion-wear processes. The latter process, termed Type I corrosion-wear, involves the repetitive mechanical degradation of the passive film that forms through aqueous corrosion. However, this is a relatively slow process.     

Discovering and using entity mappings in federated databases

In the context of a federated database containing similar information in local component databases, we consider the problem of discovering the different local representations which database designers might use to map the same entity. An extension of the normal SQL system catalog to hold additional domain metadata is discussed. This enables common local mappings to be discovered and allows SQL retrieval queries expressed in terms of the logical federated schema to be transformed to match the appropriate local database schema. The result is a practical means of coping with differing mappings in federated databases without having to resort to special higher order languages or a layer of information mediation middleware. Copyright © 1999 John Wiley & Sons, Ltd.